X-ray imaging apparatus and method for controlling the same

ABSTRACT

The X-ray imaging apparatus includes an X-ray generator to generate X-rays having at least two different energy levels and irradiate the X-rays onto a subject, a detector to detect the X-rays irradiated by the X-ray generator and transmitted through the subject, and a device to obtain images from the X-rays detected by the detector, to obtain bone image information and soft tissue image information of the subject, based on the obtained X-ray images, and to produce one image including the bone image information and the soft tissue image information.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.13/652,991 filed Oct. 16, 2012, which claims priority from Korean PatentApplication No. 10-2011-0108197, filed Oct. 21, 2011 in the KoreanIntellectual Property Office, the disclosures of which are incorporatedherein by reference in their entireties.

BACKGROUND

1. Field

Apparatuses and methods consistent with exemplary embodiments relate toobtaining an X-ray image of bones and soft tissues of a subject using aplurality of X-rays having different energy levels.

2. Description of the Related Art

An X-ray imaging apparatus irradiates an X-ray onto a subject, analyzesthe X-ray passing through the subject and, thereby, an inner structureof the subject may be observed. Since transmission of X-rays is varieddepending on the structure of the subject, the inner structure of thesubject can be imaged using an attenuation coefficient expressed as anumeral value of this variation.

Recently, methods for obtaining an X-ray image by irradiating an X-rayhaving different energy levels, instead of an X-ray with a singleenergy, have been developed and a variety of research associatedtherewith is underway.

According to one or more of these methods, an energy X-ray imagingapparatus sequentially irradiates an X-ray with a first energy and anX-ray with a second energy onto a subject to obtain a plurality oftransmission images and thereby to obtain a clear image in which bonesand soft tissue of the subject are separated using the images. However,such X-ray imaging apparatus independently outputs individual images ofbones and soft tissues, thus being disadvantageous in that it isdifficult to confirm the geometric relation between bones and softtissues and observation of a plurality of images is inconvenient.

SUMMARY

Exemplary embodiments may address at least the above problems and/ordisadvantages and other disadvantages not described above. Also,exemplary embodiments are not required to overcome the disadvantagesdescribed above, and an exemplary embodiment may not overcome any of theproblems described above.

According to an aspect of an exemplary embodiment, there is provided anX-ray imaging apparatus and a method for controlling the same forobtaining an X-ray image of bones and soft tissues using X-rays havingdifferent levels of energy, wherein one image of bones and soft tissuesis output to enable a user to confirm conditions of a subject throughone image and, at the same time, to easily confirm a relation betweenbones and soft tissues.

According to another aspect of an exemplary embodiment, there isprovided an X-ray imaging apparatus and a method for controlling thesame wherein one image of bones and soft tissues is output and the bonesand soft tissues are represented by different colors or brightness toenable a user to easily distinguish the bones from the soft tissues.

In accordance with an aspect of an exemplary embodiment, an X-rayimaging apparatus includes: an X-ray generator to generate an X-ray andirradiate the X-ray to a subject; a detector to detect the X-rayirradiated by the X-ray generator and transmitted through the subject;and a host device to obtain an image from the X-ray detected by thedetector, to obtain bone image information and soft tissue imageinformation of the subject, based on the obtained X-ray image, and toproduce and output one image including the bone image information andsoft tissue image information.

The host device may include: an image acquirer to produce one imageincluding all of the bone image information and soft tissue imageinformation; and an image output to output the image produced by theimage generator.

The image generator may make brightness of a region of bone differentfrom brightness a region of soft tissue in the one image.

The host device may further include: a color mapper to separately mapthe obtained image information onto different color channels among aplurality of color channels.

The image generator may produce one image including all of the obtainedimage information mapped onto the different color channels.

The host device may further include: an input device to receiveselection of at least one of bone and soft tissue from a user, whereinthe image generator further produces one image including imageinformation of the bone or soft tissue selected via the input device.

The host device may further include an input device to receive selectionof at least one of bone and soft tissue by a user, wherein the imagegenerator makes brightness of a region of bone or soft tissue selectedvia the input device in the one image different from brightness of aregion of a non-selected bone or soft tissue.

The host device may further include: an input device to receiveselection of one of bone image information and soft tissue imageinformation mapped onto different color channels by a user, wherein theimage generator further produces one image including only the imageinformation selected via the input device.

The host device may further include: an input device to receiveselection of one from image information mapped onto different colorchannels by a user, wherein the image generator further produces oneimage including all of the selected image information and non-selectedimage information, wherein the image generator makes brightness of aregion of bone be different from brightness a region of soft tissue inthe one image.

The color mapping performed by the color mapper may be set or varied bythe user.

The host device may further include: an input device to receiveinstruction associated with variation in weight of bone and soft tissuein the one image from a user, wherein the image generator controls theweight of bone and soft tissue in one image output from the imagegenerator depending on the input instruction.

In accordance with an aspect of an exemplary embodiment, a method forcontrolling an X-ray imaging apparatus includes: generating an X-ray andirradiating the same to a subject; detecting the X-ray transmitted intothe subject; obtaining an X-ray image from the detected X-ray; obtainingimage information of bone and soft tissue of the subject, based on theobtained X-ray image; and producing and outputting one image includingall of the obtained image information.

The producing one image may further include making brightness of aregion of bone be different from brightness a region of soft tissue inthe one image.

The method may further include: separately mapping the obtainedrespective image information onto different color channels among aplurality of color channels.

The one image may be an image including all of color channels mappedwith the obtained image information.

The method may further include: receiving selection of at least one ofbone and soft tissue by a user; and producing one image including onlyimage information of the selected bone or soft tissue.

The method may further include: receiving selection of one from colorchannels mapped with the obtained image information by a user; andproducing one image including only the selected color channel.

The method may further include: receiving selection of at least one frombones and soft tissues by a user, wherein the producing one imagefurther includes making a region of the selected bones or soft tissueimage information brighter than a region of the non-selected bones orsoft tissue image information in the one image.

The method may further include: receiving selection of one from colorchannels mapped with the obtained image information by a user, whereinthe producing one image further includes making a region of the selectedcolor channel brighter than a region of the non-selected color channelin the one image.

The method may further include: receiving instruction associated withvariation in weight of bones and soft tissues in the one image from auser; and controlling a weight of bone and soft tissue in the outputimage, depending on the input instruction.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other aspects will become more apparent by describingcertain exemplary embodiments, with reference to the accompanyingdrawings, in which:

FIG. 1 is a block diagram illustrating an X-ray imaging apparatusaccording to an exemplary embodiment;

FIG. 2 is a view illustrating an overall configuration of an X-rayimaging apparatus according to an exemplary embodiment;

FIG. 3 is a detailed block diagram illustrating a host device of anX-ray imaging apparatus according to an exemplary embodiment;

FIGS. 4A and 4B are X-ray images obtained from an X-ray imagingapparatus according to an exemplary embodiment;

FIG. 5 is a graph showing X-ray attenuation coefficients of bones andsoft tissues;

FIGS. 6A and 6B show X-ray images output from a dual energy X-rayimaging apparatus of the related art;

FIG. 7 is an example of an X-ray image output from the X-ray imagingapparatus according to an exemplary embodiment;

FIGS. 8A and 8B illustrate examples of X-ray images output from an X-rayimaging apparatus according to an exemplary embodiment;

FIG. 9 is a block diagram illustrating an X-ray imaging apparatusaccording to an exemplary embodiment;

FIG. 10 is a schematic view illustrating a data structure of one imageproduced from the X-ray imaging apparatus according to an exemplaryembodiment;

FIG. 11 is a schematic view illustrating an example of an X-ray imageproduced and output from the X-ray imaging apparatus according to anexemplary embodiment;

FIG. 12 is a block diagram illustrating an X-ray imaging apparatusaccording to an exemplary embodiment;

FIG. 13 is a block diagram illustrating an X-ray imaging apparatusaccording to an embodiment;

FIGS. 14A and 14B illustrate an example of an X-ray image output by theX-ray imaging apparatus according to an exemplary embodiment;

FIG. 15 illustrates an image output on a screen of an X-ray imagingapparatus according to an exemplary embodiment;

FIG. 16 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to an exemplary embodiment;

FIG. 17 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to an exemplary embodiment;

FIG. 18 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to an exemplary embodiment;

FIG. 19 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to an exemplary embodiment;

FIG. 20 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to an exemplary embodiment;

FIG. 21 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to an exemplary embodiment;

FIG. 22 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to an exemplary embodiment; and

FIG. 23 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to an exemplary embodiment.

DETAILED DESCRIPTION

Certain exemplary embodiments are described in greater detail below withreference to the accompanying drawings.

In the following description, like drawing reference numerals are usedfor the like elements, even in different drawings. The matters definedin the description, such as detailed construction and elements, areprovided to assist in a comprehensive understanding of exemplaryembodiments. However, exemplary embodiments can be practiced withoutthose specifically defined matters. Also, well-known functions orconstructions are not described in detail since they would obscure theapplication with unnecessary detail.

Hereinafter, an X-ray imaging apparatus according to an exemplaryembodiment will be described with reference to the accompanyingdrawings.

FIG. 1 is a block diagram illustrating an X-ray imaging apparatusaccording to an exemplary embodiment.

Referring to FIG. 1, the X-ray imaging apparatus 98 according to anexemplary embodiment includes an X-ray generator 100 to generate X-raysand irradiate the X-rays to a subject, a power supply 400 to supplypower to the X-ray generator 100, a detector 200 to detect the X-rayswhich are generated by the X-ray generator 100 and transmitted throughthe subject, and a host device 300 to obtain images detected by thedetector 200, to obtain image information of bones and soft tissues ofthe subject, based on the obtained X-ray images, and to produce andoutput one image including a plurality of pieces of image information.

The X-ray generator 100 receives power from the power supply 400,generates an X-ray and irradiates the X-ray to a subject. The energyintensity and amount of irradiated X-rays depend on the intensity andtiming of the power supplied from the power supply 400.

The power supply 400 supplies power having a predetermined voltage tothe X-ray generator 100 to generate an X-ray and the intensity of powersupplied from the power supply 400 is controlled by the host device 300.

The detector 200 detects X-rays transmitted through the subject. TheX-rays, which are irradiated by the X-ray generator 100, are transmittedthrough the subject, and, at the same time, are attenuated. Thetransmission of X-ray depends on the structure constituting a region towhich the X-ray is irradiated and the amount of transmitted X-raydepends on the position at which the X-ray is irradiated.

The structures having different X-ray transmission may be classifiedinto soft tissues such as fat, muscle and blood, tissues containing agreat amount of calcium such as bones and teeth, and gases. Accordingly,the amount of transmitted X-ray depends on the area of the subject, suchas bone, soft tissue and gas or fat tissue, to which the X-ray isirradiated.

The detector 200 includes an image intensifier and a CCD camera anddetects an X-ray transmitted through the subject, intensifies an imagethrough the image intensifier, converts the image into an electricalsignal and transfers the electrical signal to the host device 300.

The host device 300 obtains images of respective X-rays having differentenergies through image-processing, based on the transferred electricalsignal, and obtains image information associated with bones and softtissues of the subject from the obtained image. The host device 300produces and outputs an image including image information of the bonesand soft tissues.

As described above, according to an exemplary embodiment, X-ray imagesof X-rays having different energies are obtained and image informationof bones and soft tissues is obtained using the same. The methods forobtaining X-ray images of X-ray having different energies may include afirst method in which a separate irradiation is used, and a secondmethod including irradiation of X-ray, detection and separation of X-rayhaving a desired energy level.

In the first method, the X-ray generator 100 generates X-rays havingdifferent energy levels and irradiates the same to a subject, thedetector 200 detects the X-rays from the subject and sends theelectrical data to the host device 300, and the host device 300 obtainsan image of each X-ray through image-processing.

In the second method, the X-ray generator 100 irradiates an X-ray havinga predetermined level of energy once, and a photon counting detector(PCD) embodied in the detector 200 separates the X-rays according toenergy levels.

Specifically, when X-ray transmitted through the subject reaches aphotodiode region of the PCD, electrons that stay in a valence bandreceive a photon energy of X-ray and are excited to a conduction bandover a band gap energy gap. Such excitation causes production of a greatamount of electron-hole pairs even in a depletion region. Theelectron-hole pairs are moved by an electric field and a current thusflows. When the level of this current is detected, level data of X-raythat is transmitted through the subject and reaches a pixel can beobtained and an image can be obtained by collecting the data ofrespective pixels.

The PCD converts current produced according to flow of electron-holegenerated whenever a photon corresponding to the energy of X-ray isincident, into a voltage signal and intensifies the same, and inputs thesame to a comparator. The comparator compares the intensified voltagesignal with a reference voltage to output pulses and a counter countspulses output from the comparator per unit time to measure a level ofX-ray.

In an exemplary embodiment, image information of bones and soft tissuesis obtained from a plurality of images of multiple energy X-rays and oneimage including image information of the bones and soft tissues isproduced, by using, for example, one of the described-above the firstmethod or the second method to obtain a plurality of X-ray images.

In exemplary embodiments described below, the first method is describedfor convenience of description; that is, a method for obtaining aplurality of X-ray images by irradiating X-ray two or more times.

FIG. 2 is a view illustrating the overall structure of an X-ray imagingapparatus according to an exemplary embodiment.

Referring to FIG. 2, an X-ray generator 100 is mounted such that itfaces a detector 200 spaced from the X-ray generator 100 by apredetermined distance. A power supply 400 is connected to the X-raygenerator 100 to supply voltage and current, so that the X-ray generator100 generates X-rays.

The power supply 400 is controlled by the host device 300 and supplies apredetermined voltage and current to the X-ray generator 100 in order togenerate an X-ray in a test site of the subject 102.

In a case in which a human is the subject, the human assumes a posturesuitable for the site to be imaged in front of the detector 200. Forexample, in a case in which a breast is imaged, the breast of the humanis brought into contact with the detector 200 and the back of the humanfaces the X-ray generator 100. The detector 200 detects an X-ray 104that is irradiated by the X-ray generator 100 and is transmitted throughthe subject, converts the X-ray into an electrical signal and transfersthe same to the host device 300.

The host device 300 is connected to the detector 200 and the powersupply 400, transfers control signals that control voltage and currentto the power supply 400, and obtains an X-ray image of each X-ray fromthe detector 200, based on the transmitted X-ray signal. In addition,the host device 300 obtains image information of bone and soft tissueusing the difference in attenuation coefficient between the bone andsoft tissue generated in each X-ray image, and outputs an imageincluding the image information on an image output device, thus enablinga medical professional to detect whether the subject has any abnormalityand/or suffers from a disease.

The view illustrating the overall structure of the apparatus of FIG. 2is provided for description of an exemplary embodiment. The X-rayimaging may be carried out in a state in which the subject lies or sitsand the position of each constituent component is not limited to thatshown in FIG. 2 so long as the apparatus includes components performingthe desired functions.

Hereinafter, an operation of the host device 300 of the X-ray imagingapparatus according to an exemplary embodiment described with referenceto FIG. 1 will be described in detail.

FIG. 3 is a detailed block diagram illustrating a host device 300 of theX-ray imaging apparatus according to the exemplary embodiment describedwith reference to FIG. 1.

Referring to FIG. 3, in the X-ray imaging apparatus according to anexemplary embodiment, the host device 300 includes an image acquirer 311to obtain an X-ray image through image-processing of an electricalsignal transferred from the detector 200, an information acquirer 312 toobtain image information of bones and soft tissues, based on theobtained X-ray image and difference in attenuation between bones andsoft tissues, an image generator 313 to produce an image including allof the obtained image information, and an image output 314 to output theproduced image.

As discussed above, when power is supplied from the power supply 400 tothe X-ray generator 100, the X-ray generator 100 generates X-ray havingan energy corresponding to the supplied power, and the detector 200detects the X-ray that is irradiated by the X-ray generator 100 andtransmitted through the subject, and transfers the X-ray data, such aselectrical data, to the host device 300.

The X-ray generator 100 generates energy having different levelsdepending on the supplied power. In an exemplary embodiment, the numberof energy levels is not limited, but X-rays having a first energy and asecond energy having different levels are sequentially irradiated asdescribed in detail below. The sequential irradiation refers to theirradiation with the X-rays having different energy levels which are notsimultaneously irradiated onto the subject, and the irradiation order ofthe first energy level and the second energy level is not limitedthereto.

The image acquirer 311 obtains an X-ray image of the first energy and anX-ray image of the second energy through image-processing of an X-raysignal or electrical signal transferred from the detector 200. Theimage-processing method performed by the image acquirer 311 may be oneof the known image-processing methods for producing the X-ray image.

FIGS. 4A and 4B are X-ray images obtained by the image acquirer 311.FIG. 4A is an X-ray image of a first energy having a relatively lowenergy and FIG. 4B is an X-ray image of a second energy having arelatively high energy. Referring to FIGS. 4A and 4B, attenuationproperties of bones and soft tissues may be varied depending on energyintensity of the X-ray. In the information acquirer described below,image information of bones and image information of soft tissues areobtained using these properties.

The information acquirer 312 obtains image information of bones and softtissues from the X-ray image of the first energy and the X-ray image ofthe second energy obtained through the image acquirer 311, usingdifference in attenuation properties between bones and soft tissues.Hereinafter, a process for obtaining image information of bones and softtissues will be described in detail.

As described above, transmissivity or attenuation factor is varieddepending on the material through which the X-rays are transmitted. AnX-ray image is an image showing an inner structure of the subject usingthis property. The attenuation factor of the X-ray is numericallyexpressed as an attenuation coefficient. The attenuation coefficientshows a relation between intensity (Io) of the X-ray incident onto asubject and a resultant intensity (I) of the X-ray transmitted throughthe thickness (t) of the subject and is represented by the followingEquation 1.I=Io*exp(−μt)  [Equation 1]

wherein μ represents an attenuation coefficient.

Accordingly, as the attenuation coefficient increases, an intensity oftransmitted X-ray decreases. Thus, as the attenuation coefficientincreases, transmissivity of the X-ray through a subject decreases, and,as the attenuation coefficient decreases, the transmissivity of theX-ray through a subject increases.

FIG. 5 is a graph showing curves 61 and 62 of the attenuationcoefficients of the bones and soft tissues, respectively. Referring tothe graph, as the energy of X-ray increases, the values of theattenuation coefficients decrease. This means that, as energy of X-rayincreases, X-ray is more effectively transmitted through the subject. Inaddition, referring to the graph of FIG. 5, a curve 61 showing anattenuation coefficient of the bones is disposed above a curve 62showing an attenuation coefficient of the soft tissues. This means thata transmissivity of the X-ray in the soft tissue is higher than atransmissivity of the X-ray in the bone.

As can be seen from the graph of FIG. 5, a difference in two attenuationcoefficients is varied depending on the intensity of energy. Thedifference a in the attenuation coefficients between the bone and thesoft tissue at the point at which the energy of X-ray corresponds to xkeV is higher than the difference b in attenuation coefficient betweenthe bone and the soft tissue at the point at which the energy of theX-ray corresponds to y keV. That is, as the energy of X-ray decreases,the difference in the attenuation coefficients between the bone and thesoft tissue increases.

In an exemplary embodiment, a dual energy subtraction method enablingthe information acquirer 312 to obtain image information using thedifference in attenuation properties between the bone and the softtissue may be used. The dual energy subtraction method is a method forextracting image information clearly expressing the desired site ofbones and soft tissues by representing images obtained at a high energyand a low energy by a logarithm and obtaining the difference between twoimages by using an applicable weight.

I_(L) and I_(H) of the Equations 2 and 3 represent image informationexpressed as a logarithmic value of image information obtained from anX-ray with a low energy and of image information obtained from an X-raywith a high energy, respectively, and w_(b) and w_(s), representing aweight can be expressed by the Equations 4 and 5, respectively.I _(bone) =I _(L) w _(b) −I _(H)  [Equation 2]I _(soft) =I _(H) −w _(s) I _(L)  [Equation 3]w _(b)=μ_(bone)(E _(H))/μ_(bone)(E _(L))  [Equation 4]w _(s)=μ_(soft)(E _(H))/μ_(soft)(E _(L))  [Equation 5]

wherein μ_(bone) (E_(H)) represents an attenuation coefficient of thebone at a high energy,

μ_(bone) (E_(L)) represents an attenuation coefficient of the bone at alow energy,

μ_(soft) (E_(H)) represents an attenuation coefficient of the softtissue at a high energy, and

μ_(soft) (E_(L)) represents an attenuation coefficient of the softtissue at a low energy.

A weight is obtained using Equations 4 and 5 and is substituted inEquations 2 and 3 to obtain an image information I_(bone) of a bone andan image information I_(soft) of the soft tissue, respectively.

The image information of the bone is image information in whichafterimage of the soft tissue is removed and the bone is thus clearlyexpressed. The image information of the soft tissue is image informationin which afterimage of the bone is removed and the soft tissue is thusclearly expressed.

The dual energy subtraction method is provided only as an example of amethod for obtaining an X-ray image of double energy and an exemplaryembodiment is not limited to the aforementioned method.

The image generator 313 produces one image including all of imageinformation of bones and image information of soft tissues obtained fromthe information acquirer, and outputs the image through the imageoutput, to enable a user or tester to observe the condition of bones andsoft tissues from the one image.

The configuration of the image output 314 is not limited so long as itis capable of outputting and displaying an X-ray image.

FIGS. 6A and 6B illustrate X-ray images output from a dual energy X-rayimaging apparatus of the related art, and FIG. 7 illustrates an X-rayimage output from the image output of an X-ray imaging apparatusaccording to an exemplary embodiment.

Referring to FIGS. 6A and 6B, in the related art, an X-ray image showinga bone and an X-ray image showing a soft tissue are independentlyproduced and output. A user needs to separately analyze both the X-rayimage showing a bone and the X-ray image showing a soft tissue in orderto observe the condition of the subject and cannot easily analyzerelation between bone and soft tissue.

As shown in FIG. 7, the X-ray imaging apparatus according to anexemplary embodiment produces and outputs one X-ray image includingimage information of bones and soft tissues. The image information ofbones and soft tissues included in the X-ray image shows a clear imagein which afterimage of image information of bones and soft tissues isremoved from each other, allowing the user to observe the conditions ofboth the bone and the soft tissue from one image and to analyze relationbetween the bone and the soft tissue.

Hereinafter, an X-ray imaging apparatus according to another exemplaryembodiment will be described, based on exemplary embodiments describedwith reference to FIGS. 1 and 3.

The configuration of the X-ray imaging apparatus according to thisexemplary embodiment is the same as that of the exemplary embodimentdescribed with reference to FIGS. 1 and 3, except for the operation ofthe image generator. In the exemplary embodiment described withreference to FIG. 3, an image generator produces one X-ray imageincluding the image information of the bone and the image information ofthe soft tissue obtained from the information acquirer. The currentexemplary embodiment relates to one X-ray image in which the bones andthe soft tissues have different levels of brightness.

In the X-ray imaging apparatus according to this exemplary embodiment,the image generator 313 may include a brightness control filter, whichcontrols a pixel value included in a region corresponding to a bone andin a region corresponding to soft tissue in one X-ray image and therebymakes the brightness of bones different from the brightness of the softtissue. The region that is brighter among the two regions may berandomly determined by the image generator.

FIGS. 8A and 8B illustrate X-ray images output from an X-ray imagingapparatus according to an exemplary embodiment.

In the X-ray images of FIGS. 8A and 8B, a deep region, that is, a blackregion is a strongly bright region and a light region, that is, grayregion is a weakly bright region.

When the image generator 313 determines to show the bone brighter, thebone region 110 is expressed to be brighter than the soft tissue region112, as shown in FIG. 8A. The brightness control filter multiplies thevalues of all of the pixels corresponding to the image information ofthe bone in one X-ray image including the image information of the boneand the image information of the soft tissue, by a predetermined value,to intensify the visual appearance of the bone.

When the image generator 313 determines to show the soft tissuebrighter, the soft tissue region 114 is expressed brighter than the boneregion 116, as shown in FIG. 8B. The brightness control filtermultiplies the values of all of the pixels corresponding to the imageinformation of the soft tissue in one X-ray image including the imageinformation of the bone and the image information of soft tissue, by apredetermined value, to intensify the visual appearance of the softtissue.

In this exemplary embodiment, the bone and soft tissue have differentlevels of brightness. Accordingly, the brightness control filter iscapable of controlling any one region of bones and soft tissues to bedarker or lighter. That is, in this exemplary embodiment, the boneregion and the soft tissue region may be brighter or darker relative toeach other.

The exemplary embodiment described above is provided only as an exampleand any manner or filter may be used so long as it is capable of makingbone and soft tissue different from each other in brightness in oneimage.

Hereinafter, an X-ray imaging apparatus according to another exemplaryembodiment will be described.

FIG. 9 is a block diagram illustrating an X-ray imaging apparatusaccording to an exemplary embodiment.

Referring to FIG. 9, the X-ray imaging apparatus according to thisexemplary embodiment includes an X-ray generator 100 to generate X-rayshaving at least two different energy levels to be irradiated to asubject; a power supply 400 to supply power to the X-ray generator 100;a detector 200 to detect the X-rays transmitted through the subject; anda host device 300 to obtain images detected by the detector 200, toobtain respective image information of bones and soft tissues of thesubject, based on the obtained X-ray image, to map the obtained imageinformation onto different color channels and thereby produce and outputone image including all of the image information.

The X-ray generator 100, power supply 400 and detector 200 of thisexemplary embodiment are the same as those of the exemplary embodimentdescribed with reference to FIGS. 1 and 3 and a detailed descriptionthereof is thus omitted.

As shown in FIG. 9, the host device 300 according to this exemplaryembodiment includes an image acquirer 321 to perform image-processing ofan electrical signal transmitted from the detector 200 to obtain anX-ray image, an information acquirer 322 to obtain image information ofbones and soft tissues, based on the obtained X-ray image andattenuation properties of bones and soft tissues, a color mapper 323 tomap the image information of bones and soft tissues onto different colorchannels, an image generator 324 to produce one image including all ofimage information of bones and soft tissues, and an image output 325 tooutput the produced image.

The image acquirer 321 and the information acquirer 322 of thisexemplary embodiment are same as those of the exemplary embodimentdescribed with reference to FIG. 3 and a detailed description thereof isthus omitted.

The color mapper 323 maps bone image information and soft tissue imageinformation obtained from the information acquirer 322 on differentcolor channels among a plurality of color channels. Generally, an X-rayimage is expressed by brightness of black and white using a gray level,instead of the color channel, while this exemplary embodiment maps imageinformation of bones and soft tissues on a color channel to distinguishbones from soft tissues in one image by color. Any color model used forthe exemplary embodiment described with reference to FIG. 9 may be usedwithout limitation so long as it renders at least two different colors.

For example, in a case where a red-green-blue (RGB) model is used, thecolor mapper maps image information of bone and image information ofsoft tissue onto a red channel and a green channel, respectively. Theimage generator produces and outputs one image including all of theimage information of bone and image information of soft tissue or thered channel and green channel, and the bone and the soft tissue areexpressed by a red color and a green color, respectively, in one image,to easily distinguish the bone from the soft tissue.

Alternatively, the image information of bone is mapped onto the redchannel and expressed by a red color, while the image information ofsoft tissue is expressed by a gray level.

FIG. 10 is a schematic view illustrating a data structure of one imageproduced according to the exemplary embodiment described with referenceto FIG. 9.

Referring to FIG. 10, one image produced by the image generator 324 maybe divided into a plurality of pixels and each pixel includes imageinformation of bones and soft tissues. Accordingly, when the imageinformation of bones and image information of soft tissues are mappedonto the color channels having different colors, such as channel 1 andchannel 2, respectively, as shown in FIG. 10, the image information ofeach pixel is stored in the corresponding color channel.

The data structure shown in FIG. 10 is provided only as an example and amanner in which the image information of bones and soft tissues aremapped onto the color channel or a color mapped-data structure are notlimited to the aforementioned examples.

FIG. 11 is a schematic view illustrating an X-ray image produced andoutput according to the exemplary embodiment described with reference toFIG. 9.

In the X-ray image of FIG. 11, a diagonal-line pattern 120 is expressedby a green color and a dot pattern 122 is expressed by a red color.Thus, the soft tissues are expressed by a green color, while the bones,such as a rib, scapula and spine, are expressed by a red color. Inaddition, a region where bones overlap soft tissues exhibits a mixedcolor of red and green, and when the density of bones is high, the redcolor is strong, and when the density of soft tissues is high, the greencolor is strong. The user can appreciate a level of bones and softtissues present in the region through the color of the correspondingregion. It is noted that the diagonal-line pattern and dot pattern ofFIG. 11 exhibit a difference in color without concentration or densityin the X-ray image.

For example, the user observes an X-ray image showing both bones andsoft tissues through the image output 325 and then more accuratelyanalyzes only one of the X-ray image of bones and the X-ray image ofsoft tissues. Hereinafter, an X-ray imaging apparatus to selectivelyproduce and output an X-ray image of bone or soft tissue according to anexemplary embodiment will be described.

FIG. 12 is a schematic block diagram illustrating an X-ray imagingapparatus according to an exemplary embodiment.

Referring to FIG. 12, the X-ray imaging apparatus according to thisexemplary embodiment includes an X-ray generator 100 to generate X-rayshaving at least two different energy levels to be irradiated to asubject; a power supply 400 to supply power to the X-ray generator 100;a detector 200 to detect the X-rays transmitted through the subject; anda host device 300 to produce and output one image including imageinformation of bones and soft tissues and to produce and output an X-rayimage including only one of the image information of the bone and theimage information of the soft tissue, according to a selection of theuser.

The operations of the X-ray generator 100, power supply 400 and detector200 of this exemplary embodiment are the same as those of the exemplaryembodiment described with reference to FIGS. 1 and 3 and a detaileddescription thereof is thus omitted.

The host device 300 includes an image acquirer 331 to performimage-processing of an electrical signal transmitted from the detector200 to obtain an X-ray image, an information acquirer 332 to obtainimage information of bone and soft tissue, based on the obtained X-rayimage and attenuation properties of bone and soft tissue, an inputdevice 360 to receive a selection of a user, an image generator 333 toproduce one image including image information of bone and soft tissue,and an image output 334 to produce one image including only imageinformation of one of bone and soft tissue.

The operations of the image acquirer 331 and information acquirer 332 ofthis exemplary embodiment are the same as those of the exemplaryembodiment described with reference to FIG. 3 and a detailed descriptionthereof is thus omitted.

The image generator 333 first produces a combined X-ray image includingimage information of bone and soft tissue, similar to the exemplaryembodiment described with reference to FIG. 3, and the image output 334outputs this X-ray image.

The user can confirm conditions of bone and soft tissue from the outputimage and, as a result, more accurately analyzes a region in whichabnormal bone or soft tissue is present. The input device 360 is used toinput a selection of a bone or soft tissue and may be a mouse, keyboard,touch panel or the like, of the host device 300.

When the user inputs selection using the input device 360, the imagegenerator 333 produces an X-ray image including only image informationof a selected bone or soft tissue and the image output 334 outputs theproduced X-ray image. For example, when the user selects the bone, theimage generator 333 produces an X-ray image including only the imageinformation of the bone and outputs the X-ray image through the imageoutput 334, and when the user selects soft tissue, the image generator333 produces an X-ray image including only image information of the softtissue and outputs the X-ray image through the image output 334.

In this exemplary embodiment, after the X-ray image including imageinformation of the bone and soft tissue is produced and output asdescribed above with reference to FIGS. 1 and 3, the input device 360may receive a selection of the user, and the image generator may furtheroutput an X-ray image including only image information of the selectedbone or soft tissue.

As described above with reference to FIG. 8, the X-ray imaging apparatusdesignates one among bone and soft tissue through the image generatorand makes a region corresponding to bones or soft tissues designated inone image to be brighter or lighter.

An X-ray imaging apparatus may include an input device, in addition tocomponents of the X-ray imaging apparatus according to an exemplaryembodiment described with reference to FIG. 8, and the image generatormay make a region corresponding to bones or soft tissues selected by theuser to be brighter according to the user's selection.

Also, in addition to components of the X-ray imaging apparatus accordingto the exemplary embodiment described with reference to FIG. 9, anexemplary embodiment that is described below with reference to FIG. 13,further includes an input device to input selection of bone or softtissue by a user and further output the X-ray image. Hereinafter, thisexemplary embodiment will be described in detail.

FIG. 13 is a block diagram illustrating an X-ray imaging apparatusaccording to an exemplary embodiment.

Referring to FIG. 13, the X-ray imaging apparatus according to thisexemplary embodiment includes an X-ray generator 100 to generate X-rayshaving at least two different energy levels to be irradiated to asubject; a power supply 400 to supply power to the X-ray generator 100;a detector 200 to detect the X-rays transmitted through the subject; anda host device 300 to obtain images detected by the detector 200, toobtain respective image information of bone and soft tissue of thesubject, based on the obtained X-ray image, to map the obtainedplurality of image information onto different color channels, to produceand output one image including all image information, and to therebyproduce and output one image including only image information of bone orsoft tissue selected by the user.

The operations of the X-ray generator 100, power supply 400 and detector200 of this exemplary embodiment are the same as those of the exemplaryembodiments described with reference to FIGS. 1 and 3 and a detaileddescription thereof is thus omitted.

The host device 300 of this exemplary embodiment includes an imageacquirer to obtain an X-ray image through image-processing of anelectrical signal transferred from the detector 200, an informationacquirer to obtain image information of bone and soft tissue, based onthe obtained X-ray image and difference in attenuation between bone andsoft tissue, an image generator to produce an image including all of theobtained image information, an image output to output the producedimage, and an input device to receive a selection of an user.

The image acquirer 341, information acquirer 342 and color mapper 343 ofthis exemplary embodiment operate in the same manner as in the exemplaryembodiment described with reference to FIG. 9. The image generator 344and the image output 345 produce and output one X-ray image includingall of image information of bone and soft tissue in the same manner asin the exemplary embodiment described with reference to FIG. 9, andfurther operate depending on a user selection through the input device360.

The input device 360 receives a user's selection for an X-ray imageincluding only the image information of the bone or an X-ray imageincluding only image information of the soft tissue, and directly inputsselection of the bone or the soft tissue or indirectly inputs selectionvia selection of the color channels mapped with the image information ofthe bone and soft tissue.

Also, the input device 360 inputs selection of color mapping by a user,for example, the user selects mapping of bone onto a red channel andmapping of soft tissue onto a green channel, or mapping of bone onto thegreen channel and mapping of soft tissue onto the blue channel. Thecolor mapper maps image information and color channel depending on userselection.

For example, when the image information of bone is mapped onto the redchannel and image information of soft tissue is mapped onto the greenchannel, the user can select the red or green channel through the inputdevice.

The image generator produces one X-ray image including only imageinformation of bone or soft tissue selected by the user and outputs theimage through the image output 345. For example, when the user selectssoft tissue, the image generator produces one X-ray image including onlyimage information of the soft tissue, and when the user selects a greenchannel mapped onto soft tissue, the image generator 344 produces oneX-ray image only including the green channel.

The X-ray image including only a green channel is the same as an X-rayimage including only image information of soft tissue, and directselection of bone or soft tissue and indirect selection via the colorchannel are only different from each other in terms of input manner ofinput device and produce substantially identical results.

FIGS. 14A and 14B illustrate X-ray images output by the X-ray imagingapparatus according to the exemplary embodiment described with referenceto FIG. 13.

The X-ray imaging apparatus according to this exemplary embodiment firstoutputs an X-ray image of FIG. 11 discussed above, receives a selectionof a user through the input device, and outputs an X-ray image accordingto the selection. When the user selects bone or a red channel mappedwith image information of bone, an X-ray image including only imageinformation of the bone is produced and output, as shown in FIG. 14A,and only the bone expressed by a red color is observed in the X-rayimage. On the other hand, when the user selects the soft tissue or agreen channel mapped with image information of soft tissue, as shown inFIG. 14B, an X-ray image including only image information of the softtissue is produced and output and only the soft tissue expressed by agreen color is observed in the X-ray image.

The user can obtain information associated with a test site of thesubject in need of more detailed analysis from the X-ray image shown inFIGS. 14A and 14B.

This exemplary embodiment is similar to the exemplary embodimentassociated with the X-ray imaging apparatus described with reference toFIG. 8 and can make the selected region relatively brighter. Referringto the block diagram of FIG. 13, when the user selects any one of boneand soft tissue through the input device 360, this exemplary embodimentmakes a region corresponding to a selected bone or soft tissue brighterthan a non-selected region in the one image produced by the imagegenerator 344. The image generator may include a brightness controlfilter.

The image output 345 may output an image with a controlled brightnessand the user may more accurately observe the desired test site throughthe output image and, at the same time, can confirm a relation betweenthe selected region and the non-selected region.

The X-ray imaging apparatuses according to exemplary embodimentsdescribed above produce and output one X-ray image including all ofimage information of bone and soft tissue, and further produce andoutput one X-ray image including only image information of bone or softtissue. In the X-ray imaging apparatus according to an exemplaryembodiment that will be described with reference to FIG. 15, the usercan change a weight of the bone and soft tissue in the same X-ray image.

The X-ray imaging apparatus according to this exemplary embodimentincludes an X-ray generator 100, a power supply 400, a detector 200 anda host device 300, and the operations of the X-ray generator 100, thepower supply 400 and the detector 200 are the same as those of theexemplary embodiment described with reference to FIG. 12 and a detaileddescription thereof is thus omitted.

The host device 300 includes an image acquirer 331, an informationacquirer 332, an image generator 333, an input device 360 and an imageoutput 334. Operations of the image acquirer and information acquirer ofthis exemplary embodiment are also the same as those of the exemplaryembodiment described with reference to FIG. 12.

The image generator 333 produces and outputs one image including all ofimage information of bone and soft tissue, and the input device 360receives user instructions associated with variation in weight of boneand soft tissue. The input device may be a keyboard, mouse or touchpanel or a predetermined member movable or rotatable by the user.

FIG. 15 illustrates an image output by an X-ray imaging apparatusaccording to an exemplary embodiment.

Referring to FIG. 15, the image generator produces one X-ray imageincluding image information of bone and soft tissue, based on a weightratio of bone and soft tissue of 1:1 and outputs the image on a screen314 of the image output. The output of image through the image output isperformed after generation of the image by the image generator and thedetailed description of this process will be omitted.

The image output outputs an X-ray image having a weight ratio of 1:1together with a control bar 316 as shown in FIG. 15. The control bar canmove up and down and the user can move the control bar using a cursor ofa mouse or a keyboard arrow or through touch by hand when the imageoutput is a touch panel.

When the first output image is an image having a weight ratio of 1:1, asthe control bar is moved up, the weight of the bone increases, and whenthe control bar is moved down, the weight of the soft tissue increasesand vice versa. In FIG. 15, an X-ray image displayed on the left of thescreen 314 is changed to an X-ray image displayed on the right thereofaccording to movement of control bar, and variation in weight iscontinuous and variation in X-ray image is thus also continuous.

As shown on the right side of FIG. 15, as the control bar moves up, thebones are stressed in the X-ray image, and, as the control bar movesdown, the soft tissues are stressed. The user observes and confirms anoutput X-ray image and selects the desired X-ray image, while moving acontrol bar.

FIG. 15 is provided only as an exemplary embodiment, and a weight ratioof an initially output image may be different from 1:1. Also, theconfiguration of the image output is not limited to the configurationshown in FIG. 15.

For example, the described-above varied weight ratio may be applied toan exemplary embodiment described with reference to FIG. 9. For example,the image generator produces one image including all of mapped colorchannels, outputs the image through the image generator and, when theuser inputs instructions associated with variation in weight of the boneand soft tissue through the input device, a weight ratio of bone to softtissue is controlled in the X-ray image displayed by the image output.The X-ray image output by the image output may be similar to the X-rayimage of FIG. 15, except that a color is mapped on the bone and softtissue.

Hereinafter, a method for controlling an X-ray imaging apparatusaccording an exemplary embodiment will be described.

FIG. 16 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to an exemplary embodiment.

Referring to FIG. 16, an X-ray is generated and irradiated to a subject,in operation 510. The X-ray transmitted through the subject is detected,in operation 511. X-ray images having respective energies are obtainedbased on the detected X-ray, in operation 512. The energy means anenergy having different levels.

Image information of bone and soft tissue are obtained from the obtainedX-ray image, using difference in attenuation properties of bone and softtissue, in operation 513, and one image including all of imageinformation of bone and soft tissue is produced and output, in operation514.

Similar to the X-ray imaging apparatus as described above, in order toobtain X-ray images having different energy levels, the X-rays havingdifferent energy levels are separately irradiated, or an X-ray having apredetermined energy level is irradiated once, and the X-ray is thenseparated from X-rays having different energy levels using PCD. In anexemplary embodiment, the two methods may be used.

Hereinafter, an exemplary embodiment using separate irradiation ofX-rays having different energy levels will be described.

FIG. 17 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to an exemplary embodiment.

Referring to FIG. 17, an energy of X-ray to be irradiated is set, inoperation 610. An X-ray having a predetermined energy is irradiated ontoa subject by supplying power corresponding to the set energy to theX-ray generator 100, in operation 611. The value of set energy dependson the area for which a diagnosis is sought. For example, in breastimaging, an X-ray having a high energy is primarily irradiated bysupplying a tube voltage of 110 kVp and a tube current of 120 mA.

The detector 200 detects the X-ray transmitted through the subject andconverts the X-ray into an electrical signal, in operation 612. Theimage acquirer obtains an X-ray image, based on the detected X-ray, inoperation 613. That is, the converted electrical signal is transmittedto the host device 300 and the image acquirer obtains an X-ray imagethrough image-processing of the electrical signal.

In operation 614, it is determined whether an X-ray is to be furtherirradiated. An exemplary embodiment relates to an X-ray imagingapparatus which performs irradiation of X-ray at least two times and thenumber of irradiations depends on the number of energy levels to beused.

As a result of the determination, when an X-ray is to be furtherirradiated (“yes”), the energy level of X-ray to be irradiated is resetsuch that it is different from the energy level of the previouslyirradiated X-ray, in operation 615, and an X-ray having the reset energylevel is irradiated to a subject, in operation 611. Also, the detectionof X-ray using the detector 200 and obtaining an X-ray image using theimage acquirer are repeated.

Unless an X-ray is further irradiated, the information acquirer obtainsimage information of bone and soft tissue from the obtained X-ray imageusing difference in X-ray attenuation properties of bone and softtissue, in operation 616.

The image generator produces one X-ray image including all of theobtained bone image information and soft tissue image information andoutputs the X-ray image through the image output, in operation 617.

FIG. 18 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to the exemplary embodiment described withreference to FIG. 8.

Similarly to an exemplary embodiment described above with reference toFIG. 17, an energy of X-ray is set, in operation 620, the X-ray isirradiated to the subject, in operation 621, the X-ray transmittedthrough the subject is detected and converted into an electrical signal,in operation 622, an X-ray image is obtained through image-processing,in operation 623, and whether further to irradiate an X-ray isdetermined, in operation 624. When an X-ray is further irradiated, theenergy level of X-ray to be irradiated is reset such that it isdifferent from the energy level of the previously irradiated X-ray, inoperation 625, and the aforementioned process is repeated with the resetenergy of X-ray.

The information acquirer obtains image information of bone and softtissue from the obtained X-ray image using difference in X-rayattenuation properties between bone and soft tissue, in operation 626,and the image generator produces one image including all of imageinformation of bone and soft tissue, in operation 627.

A bone region and a soft tissue region are controlled to be differentfrom each other in brightness in one image. Specifically, the imagegenerator makes one of the bone and soft tissue region brighter ordarker than the other region using a brightness control filter. Thisaims to distinguish bone from soft tissue in one X-ray image usingdifference in brightness levels. The bone region and soft tissue regionmay be different from each other and any of the bone region or the softtissue region may be brighter or darker.

The X-ray image in which bone and soft tissue are controlled to bedifferent in brightness is output through the image output, in operation628.

FIG. 19 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to the exemplary embodiment described withreference to FIG. 9.

Similarly to what is described above, an energy of X-ray is set, inoperation 630, the X-ray is irradiated to a subject, in operation 631,the X-ray transmitted through the subject is detected and converted intoan electrical signal, in operation 632, an X-ray image is obtainedthrough image-processing, in operation 633, whether further to irradiatean X-ray is determined, in operation 634, and the aforementioned processis repeated while resetting an energy level of X-ray, in operation 635.

The information acquirer obtains image information of bone and softtissue from the obtained X-ray image using difference in X-rayattenuation properties between bone and soft tissue, in operation 636,and the color mapper maps obtained respective image information ontodifferent color channels, in operation 637. A detailed explanation ofcolor mapping is described above with reference to FIG. 9.

The image generator produces one image including all of mapped colorchannels and outputs the image through the image output, in operation638. That is, the image generator produces and outputs one imageincluding all of image information of the bone and soft tissue. A usercan simultaneously determine conditions of the bone and soft tissuethrough one X-ray image in which the bone and soft tissue arerepresented by different colors.

FIG. 20 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to the exemplary embodiment described withreference to FIG. 12.

The operations 640, 641, 642, 643, 644, 645, 646, and 647 correspond tothe respective operations 620 to 627 of an exemplary embodimentdescribed with reference to FIG. 18 and a detailed description thereofis thus omitted.

After one image including all of image information of the bone and softtissue is output, a user selects one from bone and soft tissue, inoperation 648. In operation 649, it is determined whether the userselected the bone (“yes”), and an X-ray image including only imageinformation of the bone is produced and output, in operation 650. If itis determined that the user selected soft tissue, in operation 649(“No”), one X-ray image including only image information of the softtissue is produced and output, in operation 651.

FIG. 21 is a flowchart illustrating a method for controlling the X-rayimaging apparatus according to an exemplary embodiment.

Similar to what is described above, an energy of X-ray is set, inoperation 670, the X-ray is irradiated to the subject, in operation 671,the X-ray transmitted through the subject is detected and converted intoan electrical signal, in operation 672, an X-ray image is obtainedthrough image-processing, in operation 673, whether further to irradiatean X-ray is determined, in operation 674, and the aforementioned processis repeated while resetting an X-ray energy level, in operation 675.

The information acquirer obtains image information of bone and softtissue from the obtained X-ray image using difference in X-rayattenuation properties between the bone and soft tissue, in operation676, and the image generator produces and outputs one image includingall of image information of the bone and soft tissue, in operation 677.

The user inputs selection of one from bone and soft tissue, in operation678. In operation 679, it is determined whether the user selected thebone (“yes”). Accordingly, in one image, a region corresponding to thebone is controlled to be output brighter than a region corresponding tosoft tissue, in operation 680. If it is determined that the userselected the soft tissue, in operation 679, the region corresponding tothe soft tissue is controlled to be output brighter than the regioncorresponding to the bone, in operation 681. The brightness of the boneand soft tissue may be relative to each other and brightness of theregion corresponding to a non-selected bone or soft tissue may bereduced in order to brighten the region corresponding to a selected boneor soft tissue.

FIG. 22 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to the exemplary embodiment described withreference to FIG. 13.

The operations 690, 691, 692, 693, 694, 695, 696, 697, and 698correspond to the operations 630 to 638, respectively, described abovewith reference to FIG. 19 and a detailed description thereof is thusomitted.

Accordingly, the X-ray image in which the bone and soft tissue aredistinguished from each other via different colors is produced andoutput, in operation 698. In operation 699, in a user may select onefrom the bone and soft tissue. When the user inputs a selection of thebone (“yes”), an X-ray image including only the image information of thebone is produced and output, in operation 700. When the user inputsselection of soft tissue, in operation 699 (“No”), an X-ray imageincluding only image information of the soft tissue is produced andoutput, in operation 701.

When the user inputs a selection, the user may select, rather than oneof bone and soft tissue, one of the color channels mapped with the boneand soft tissue, respectively. In this case, one X-ray image includingonly the selected color channel is produced and output, and the resultsthus obtained are the same as those of the case in which bone or softtissue are selected.

FIG. 23 is a flowchart illustrating a method for controlling an X-rayimaging apparatus according to the exemplary embodiment described withreference to FIG. 15.

The operations 710, 711, 712, 713, 714, 715, 716, and 717 correspond tothe operations 610 to 617 described above with reference to FIG. 17 anda detailed description thereof is thus omitted.

When an X-ray image is produced and output, a weight ratio of the boneto soft tissue in one image may be 1:1 or may be changed.

The user inputs instructions to change the weight ratio of the bone andsoft tissue, in operation 718. Input of instructions may be carried outusing a keyboard, mouse, touch panel, movable member or the like.

The image generator controls a weight ratio of the bone to soft tissuein one image according to the input instruction, in operation 719, andoutputs the image having the changed weight ratio through the imageoutput, in operation 730. The output may be carried out by changing aweight ratio of the bone to soft tissue in the output X-ray image.

The methods for obtaining an X-ray image described with reference toFIGS. 17 to 23 are carried out by irradiating an X-ray at differentenergy levels to obtain images of respective X-rays having differentenergy levels. However, in any of exemplary embodiments, X-rays havingvarious energies and X-ray images associated therewith may be obtainedusing PCD by irradiating an X-ray once, as described above withreference to FIG. 16.

As apparent from the foregoing, an exemplary embodiment provides anX-ray imaging apparatus and a method for controlling the same forobtaining an X-ray image of the bones and soft tissues using X-rayshaving different levels of energy, wherein one image of bones and softtissues is output to enable a user to confirm conditions of a subject byobtaining only one image and, at the same time, to easily confirm arelation between the bones and soft tissues.

An exemplary embodiment provides an X-ray imaging apparatus and a methodfor controlling the same wherein one image of bones and soft tissues isoutput and the bones and soft tissues are represented by differentcolors or brightness levels to enable a user to easily distinguish thebones from the soft tissues and thereby to improve accuracy andefficiency of diagnosis.

Although a few exemplary embodiments have been shown and described, itwould be appreciated by those skilled in the art that changes may bemade in the exemplary embodiments without departing from the principlesand spirit of the invention, the scope of which is defined in the claimsand their equivalents.

What is claimed is:
 1. An X-ray imaging apparatus comprising: an X-raysource which irradiates an X-ray onto a subject; a detector whichdetects the X-ray transmitted through the subject; and a device whichobtains an X-ray image data from the X-ray detected by the detector,obtains bone image information and soft tissue image information of thesubject, based on the obtained X-ray image data, and produces one imageincluding the bone image information and the soft tissue imageinformation.
 2. The X-ray imaging apparatus according to claim 1,wherein the device comprises: an image generator which produces the oneimage including the bone image information and the soft tissue imageinformation; and an image output device which outputs the one imageproduced by the image generator.
 3. The X-ray imaging apparatusaccording to claim 2, wherein the image generator adjusts a brightnessof a bone region to be different from a brightness a soft tissue regionin the one image.
 4. The X-ray imaging apparatus according to claim 2,wherein the device further comprises: a color mapper which separatelymaps the obtained bone image information and the obtained soft tissueimage information onto a first color channel and a second color channelhaving color different from the first color channel.
 5. The X-rayimaging apparatus according to claim 4, wherein the image generatorproduces the one image including the obtained bone image information andthe obtained soft tissue image information which have been mapped ontothe first and second color channels.
 6. The X-ray imaging apparatusaccording to claim 2, wherein the device further comprises: an inputdevice which receives a selection of at least one of a bone and a softtissue, from a user, wherein the image generator further producesanother image including only the image information of the bone or thesoft tissue selected via the input device.
 7. The X-ray imagingapparatus according to claim 3, wherein the device further comprises aninput device which receives a selection of at least one of the boneregion and the soft tissue region, from a user, wherein the imagegenerator adjusts the brightness of a selected one of the bone region orthe soft tissue region in the one image to be different from thebrightness of a non-selected one of the bone region or the soft tissueregion.
 8. The X-ray imaging apparatus according to claim 5, wherein thedevice further comprises: an input device which receives a selection ofone of the bone image information and the soft tissue image informationmapped onto the first and second color channels, from a user, whereinthe image generator further produces another image including only one ofthe bone image information or the soft tissue image information selectedvia the input device.
 9. The X-ray imaging apparatus according to claim5, wherein the device further comprises: an input device which receivesa selection of one of the bone image information and the soft tissueimage information mapped onto the first and second color channels, froma user, wherein the image generator further produces the one imageincluding a selected image information and a non-selected imageinformation, and adjusts a brightness of a region of the bone to bedifferent from a brightness of a region of the soft tissue in the oneimage.
 10. The X-ray imaging apparatus according to claim 4, whereincolor mapping performed by the color mapper is set or changed by a user.11. The X-ray imaging apparatus according to claim 2, wherein the devicefurther comprises: an input device which receives an instruction tochange weights of the bone and the soft tissue in the one image, from auser, wherein the image generator controls the weights of the bone andthe soft tissue in the one image output by the image output device basedon the input instruction.
 12. The X-ray imaging apparatus according toclaim 1, wherein the device comprises: an image output device configuredto output the one image as a combination image including both theobtained bone image information and the obtained soft tissue imageinformation.
 13. The X-ray imaging apparatus according to claim 12,wherein the device further comprises an input device comprising a userinterface comprising a sliding scale configured to receive aninstruction to increase or decrease weights of the bone and the softtissue, respectively, in the one image, and the image output deviceoutputs the one image in which an intensity of the obtained bone imageinformation or the obtained soft tissue image information isrespectively increased or decreased based on respective input receivedfrom the sliding scale.
 14. The X-ray imaging apparatus according toclaim 1, wherein the detector comprises a flat panel detector.
 15. TheX-ray imaging apparatus according to claim 1, wherein the X-rayirradiated by the X-ray source has an energy level including a firstenergy level and a second energy level, and the detector is configuredto separate the detected X-ray according to the first energy level andthe second energy level.
 16. The X-ray imaging apparatus according toclaim 2, wherein the device further comprises: a color mapper configuredto separately map the bone image information onto a first color channelor the soft tissue image information onto a second color channel havinga color different from that of the first color channel.
 17. The X-rayimaging apparatus according to claim 16, wherein at least one of thebone image information and the soft tissue image information of the oneimage is mapped onto the first color channel or the second colorchannel.
 18. The X-ray imaging apparatus according to claim 2, whereinthe device further comprises: an input device configured to receive aninstruction to change weights of the bone or the soft tissue in the oneimage, from a user, wherein the image generator is configured to controlthe weights of the bone or the soft tissue in the one image output bythe image output device based on the input instruction.
 19. A method forcontrolling an X-ray imaging apparatus, the method comprising:irradiating an X-ray onto a subject; detecting the X-ray transmittedthrough the subject; obtaining an X-ray image data from the detectedX-ray; obtaining image information of a bone and a soft tissue of thesubject, based on the obtained X-ray image data; and producing one imageincluding the obtained image information.
 20. The method according toclaim 19, wherein the producing the one image further comprisesadjusting a brightness of a region of the bone to be different from abrightness of a region of the soft tissue in the one image.
 21. Themethod according to claim 19, further comprising: separately mapping theobtained image information of the bone and the soft tissue,respectively, onto a first color channel and a second color channelhaving color different from the first color channel.
 22. The methodaccording to claim 21, wherein the one image is an image including dataof the first and second color channels mapped with the obtained imageinformation.
 23. The method according to claim 19, further comprising:receiving a selection of at least one of the bone and the soft tissue,from a user; and producing another image including only the imageinformation of the selected bone or the selected soft tissue.
 24. Themethod according to claim 22, further comprising: receiving a selectionof one of the first or second color channels mapped with the obtainedimage information, from a user; and producing another image includingonly the selected color channel.
 25. The method according to claim 20,further comprising: receiving a selection of at least one of the boneand the soft tissue, from a user, wherein the producing the one imagefurther comprises adjusting a region of a selected one of the bone orthe soft tissue to be brighter than a region of a non-selected one ofthe bone or the soft tissue, in the one image.
 26. The method accordingto claim 22, further comprising: receiving a selection of one of thefirst or second color channels mapped with the obtained imageinformation, from a user, wherein the producing the one image furthercomprises adjusting a region of a selected one of the first and secondcolor channels to be brighter than a region of a non-selected one of thefirst and second color channels, in the one image.
 27. The methodaccording to claim 19, further comprising: receiving an instruction tochange weights of the bone and the soft tissue in the one image, from auser; and controlling the weights of the bone and the soft tissue in theoutput image, depending on the input instruction.
 28. A non-transitorycomputer-readable storage medium storing a program, which when executedby a computer, causes the computer to perform a method comprising:irradiating an X-ray onto a subject; detecting the X-ray transmittedthrough the subject; obtaining an X-ray image data from the detectedX-ray; obtaining image information of a bone and a soft tissue of thesubject, based on the obtained X-ray image data; and producing one imageincluding the obtained image information.
 29. The non-transitorycomputer-readable storage medium according to claim 28, wherein theproducing the one image further comprises adjusting a brightness of aregion of the bone to be different from a brightness of a region of thesoft tissue.
 30. The non-transitory computer-readable storage mediumaccording to claim 28, wherein the method further comprises: separatelymapping the obtained image information of the bone and the soft tissueonto a first color channel and a second color channel having colordifferent from the first color channel.
 31. A method for controlling anX-ray imaging apparatus, the method comprising: generating X-rays havingat least two different energy levels different from one another andirradiating the X-rays having the different energy levels onto asubject; detecting the X-rays transmitted through the subject; obtainingan X-ray image data from the detected X-rays; obtaining imageinformation of a bone and a soft tissue of the subject, based on theobtained X-ray image data; and producing one image including theobtained image information.
 32. An X-ray imaging apparatus comprising:an X-ray source configured to irradiate an X-ray onto a subject; and adevice configured to obtain bone image information and soft tissue imageinformation of the subject, based on the X-ray transmitted through thesubject, and produce one image including the bone image information andthe soft tissue image information.
 33. The X-ray imaging apparatusaccording to claim 32, wherein the device comprises: an image generatorconfigured to produce the one image including the bone image informationand the soft tissue image information; and an image output deviceconfigured to output the one image produced by the image generator. 34.The X-ray imaging apparatus according to claim 33, wherein the devicefurther comprises: a color mapper configured to separately map the boneimage information onto a first color channel or the soft tissue imageinformation onto a second color channel having a color different fromthat of the first color channel.
 35. The X-ray imaging apparatusaccording to claim 34, wherein at least one of the bone imageinformation and the soft tissue information of the one image is mappedonto the first color channel or the second color channel.
 36. The X-rayimaging apparatus according to claim 33, wherein the device furthercomprises: an input device configured to receive an instruction tochange weights of the bone or the soft tissue in the one image, from auser, wherein the image generator is configured to control the weightsof the bone or the soft tissue in the one image output by the imageoutput device based on the input instruction.
 37. An X-ray imagingapparatus comprising: an X-ray source configured to irradiate an X-rayonto a subject; a detector configured to detect the X-ray transmittedthrough the subject; and a device comprising: an information acquirerconfigured to obtain bone image information and soft tissue imageinformation of the subject, based on the detected X-ray; an imagegenerator configured to produce one image including the bone imageinformation and the soft tissue image information; an image outputdevice configured to output the one image produced by the imagegenerator; and an input device configured to receive an instruction tochange weights of the bone or the soft tissue in the one image, from auser, wherein the image generator is configured to control the weightsof the bone or the soft tissue in the one image output by the imageoutput device based on the input instruction.
 38. An X-ray imagingapparatus comprising: an information acquirer configured to obtain boneimage information and soft tissue image information of a subject, basedon a plurality of X-ray images of the subject corresponding to aplurality of energy levels; and an image generator configured to produceone image including the bone image information and the soft tissue imageinformation.
 39. The X-ray imaging apparatus according to claim 38,further comprising: an image output device configured to output the oneimage produced by the image generator.
 40. The X-ray imaging apparatusaccording to claim 38, further comprising: a color mapper configured toseparately map the bone image information onto a first color channel orthe soft tissue image information onto a second color channel having acolor different from that of the first color channel.
 41. The X-rayimaging apparatus according to claim 39, further comprising: an inputdevice configured to receive an instruction to change weights of thebone or the soft tissue in the one image, from a user, wherein the imagegenerator is configured to control the weights of the bone or the softtissue in the one image output by the image output device based on theinput instruction.
 42. An X-ray imaging apparatus comprising: an X-raysource configured to irradiate an X-ray onto a subject; a detectorconfigured to detect the X-ray transmitted through the subject; and adevice configured to obtain X-ray image data from the X-ray detected bythe detector, obtain bone image information and soft tissue imageinformation of the subject, based on the obtained X-ray image data,separately map the bone image information onto a first color channel orthe soft tissue image information onto a second color channel having acolor different from that of the first color channel and produce oneimage including the bone image information and the soft tissue imageinformation.